Sources and sinks of methane in wetland ecosystem using multi-scale flux measurements, stable carbon isotope signal and microbial genomics
Northern peatlands are one of the main terrestrial carbon reservoirs and a key feature of the boreal landscape. Current climate change threatens the functioning of these ecosystems and hence the fate of their carbon reservoir is highly uncertain; e.g. mires in Southern Sweden have shrubified in the past 100 years for unknown reasons.
The diversity of plant communities in mire ecosystems reflects the mosaic of their microtopographic features. We can assume that the differences in the quality of the organic material provided by different plant communities is reflected in the diversity of microbial communities. These microbial communities are responsible for processing carbon compounds and as such control to a large part the greenhouse gas (GHG) budgets of mires.
The change in vegetation and associated microbial communities can thus alter the GHG budgets of mire ecosystems. Of these, especially methane (CH4) is of great importance, as it partially counteracts the mitigating effect of increased carbon dioxide (CO2) uptake. Wetland ecosystems are the largest source of methane in Sweden and the largest natural source globally.
The mosaic-like nature of wetland vegetation results in spatially varying CH4 emissions. Similarly, the responses of vegetation communities to changing climate occur in this mosaic.
The main aim of the proposed project was to better constrain methane emissions from the microtopographic mosaic of the mire ecosystem and to upscale it from microbial community level to ecosystem and landscape scale.